Publications

Résumé In this paper, we propose a new variance reduction method for quantile regressions with endogeneity problems, for alpha-mixing or m-dependent covariates and error terms. First, we derive the asymptotic distribution of two-stage quantile estimators based on the fitted-value approach under very general conditions. Second, we exhibit an inconsistency transmission property derived from the asymptotic representation of our estimator. Third, using a reformulation of the dependent variable, we improve the efficiency of the two-stage quantile estimators by exploiting a tradeoff between an inconsistency confined to the intercept estimator and a reduction of the variance of the slope estimator. Monte Carlo simulation results show the fine performance of our approach. In particular, by combining quantile regressions with first-stage trimmed least-squares estimators, we obtain more accurate slope estimates than 2SLS, 2SLAD and other estimators for a broad set of distributions. Finally, we apply our method to food demand equations in Egypt.
Mots clés Two-stage estimation, Variance reduction, Quantile regression, Asymptotic bias
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Résumé We study the dynamics of risk-sharing cooperatives among heterogeneous agents. Based of their knowledge on their risk exposure and the performance of the cooperatives, agents choose whether or not to remain in the risk-sharing agreement. We highlight the key role of other-regarding preference (altruism and inequality aversion) in stabilizing less segregated (and smaller) cooperatives. Limited knowledge and learning of own risk exposure also contributes to reducing segregation, the two effects (of learning and other-regarding preferences) being complementary. Our findings shed light on the mechanisms behind risk-sharing agreements between agents heterogeneous in their risk exposure.
Mots clés Risk-sharing, Agent-based, Cooperative, Learning, Altruism, Other-regarding preferences
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Résumé Les sites qui proposent à leurs utilisateurs de reconstituer en ligne leur arbre généalogique fleurissent sur Internet. Cet article analyse le travail de collecte et de saisie effectué par ces utilisateurs et comment il pourrait être utilisé en démographie historique, afin de compléter la connaissance des générations du passé. Pour cela, les résultats obtenus à partir de la base Geneanet sont confrontés à ceux connus de la littérature, et concernent les enregistrements de 2 457 450 individus français ou d'origine française ayant vécu au xixe siècle. Est ainsi mis en évidence un biais important du rapport de masculinité (sous-représentation des femmes). La fécondité est elle aussi fortement sous-estimée. Quant à la mortalité, (par comparaison aux valeurs historiques), ces données sous-estiment la mortalité des hommes jusqu’à 40 ans environ et celle des femmes jusqu’à 25 ans, puis elles la surestiment. Enfin, la richesse des caractéristiques spatiales contenues dans les arbres généalogiques est également exploitée pour produire de nouvelles données sur les migrations internes au xixe siècle.
Mots clés Fertility, Genealogy, Collaborative data, Historical demography, Mortality, Migration, Démographe historique, Fécondité, Généalogie, Migration, Longévité, Données collaboratives
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Résumé This study investigates the differences between zombie firms and non-zombie firms in corporate social responsibility activities such as reporting, disclosure and fulfillment. Using Chinese listing company data collected from 2009 to 2016, we apply a three stage model with a double Heckman correction to deal with potential self-selection/endogeneity bias and to measure the differences consistently. We found that zombie firms are less willing to release standalone corporate social responsibility reports than non-zombie firms. Among companies that release standalone corporate social responsibility reports, the corporate social responsibility disclosure of zombie firms is at least not worse than non-zombie firms, but the corporate social responsibility fulfillment is significantly lower. We conclude from this gap between disclosure and fulfillment to the hypocritical behavior of zombie firms, due to the absence of control in corporate social responsibility. We suggest that government should enhance supervision over zombie firms’ corporate social responsibility activities and subsidies towards them in order to lower their economic damage. Supplementary analyses provide some clues concerning the heterogeneity of inconsistence in term of external support characteristics, ownership and censorship which require further studies.
Mots clés Hypocrisy, Fulfillment, Disclosure, Reports, Zombie firms, Corporate social responsibility
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Résumé We consider an economy with three cities producing different outputs. Two cities produce intermediate goods, a type 1 city producing an intermediate “agricultural” good with capital and labor only, and a type 2 city producing an intermediate “industrial” good with capital, labor, and human capital. A type 3 city produces the final good which is obtained from the two intermediate goods and labor. The asymmetric introduction of human capital allows us to prove that the three cities experience, at equilibrium, heterogeneous endogenous growth rates which are proportional to the growth rate of human capital. We show that the “industrial” type 2 city is characterized by the larger growth rate while the “agricultural” type 1 city experiences the lower growth rate, and thus the type 3 city is characterized by a growth rate which is a convex combination of the two former growth rates. This implies that the relative size in terms of output of the “agricultural” city decreases over time. This property allows us to recover the empirical fact that most non-agricultural production occurs in growing metropolitan areas. But, simultaneously, as we prove that total labor employed in each city is proportional to the total population, the relative population size distribution of cities is constant over time, as shown in empirical studies.
Mots clés Urban dynamics, Human capital, Heterogeneous growth rates, Endogenous growth, City inequalities
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Résumé TIP curves are cumulative poverty gap curves used for representing the three different aspects of poverty: incidence, intensity and inequality. The paper provides Bayesian inference for TIP curves, linking their expression to a parametric representation of the income distribution using a mixture of log-normal densities. We treat specifically the question of zero-inflated income data and survey weights, which are two important issues in survey analysis. The advantage of the Bayesian approach is that it takes into account all the information contained in the sample and that it provides small sample credible intervals and tests for TIP dominance. We apply our methodology to evaluate the evolution of child poverty in Germany after 2002, providing thus an update the portrait of child poverty in Germany given in Corak et al. (Rev. Income Wealth 54(4), 547–571, 2008).
Mots clés Bayesian inference, Survey weights, Mixture model, Zero-inflatedmodel, Inequality, Poverty
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Résumé L’évasion fiscale est un sujet qui se dérobe aux outils de l’analyse économique traditionnelle. D’une part, comme toute activité illégale, l’évasion fiscale échappe à l’observation du chercheur en même temps qu’elle se dissimule aux autorités : l’analyse empirique de son ampleur, de ses déterminants et de la manière dont différents dispositifs l’affectent est nécessairement très limitée. D’autre part, sur le plan théorique, l’application simple du calcul coût-bénéfice auquel est supposé se livrer le contribuable « rationnel » conduit à un paradoxe : contrairement à une idée largement répandue, les bénéfices de l’évasion fiscale sont tellement élevés, et le risque de sanction est tellement faible, que l’on peut s’étonner qu’elle soit aussi peu pratiquée dans l’ensemble des économies développées. Plutôt que l’évasion fiscale, c’est donc la « soumission fiscale » qui en constitue le pendant, la disposition à payer l’impôt, qu’il convient d’expliquer pour en comprendre les déterminants. Le double défi que posent les décisions d’évasion fiscale à l’analyse économique n’a pu être relevé que très récemment, grâce à l’émergence, au cours des vingt dernières années, d’une nouvelle approche, l’économie comportementale, qui s’appuie sur la psychologie pour mieux comprendre les comportements économiques ; et, conjointement, d’une nouvelle méthode, l’économie expérimentale, qui permet d’étudier empiriquement les comportements économiques sur lesquels il est difficile de collecter des données convaincantes. Cet opuscule rend compte des résultats de ces travaux et présente un panorama des outils de politique fiscale qui s’en dégagent.
Mots clés Economie politique, Aspect psychologique, Lutte contre, Fraude fiscale
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Résumé Does drawing economic benefit from nature impinge on conservation? This has been a subject of controversy in the literature. The article presents a management method to overcome this possible dilemma, and reconcile conservation biology with economics. It is based on recent advances in the mathematical theory of dynamic systems under viability constraints. In the case of a one-locus two-allele plant coexisting with a one-locus two-allele parasite, the method provides a rule for deciding when and to what extent the resistant or the susceptible strain should be cultivated, in the uncertain time-varying presence of the parasite. This is useful for preventing the fixation of the susceptible allele - and thereby limiting the plant's vulnerability in the medium term, should the parasite reappear. The method thus provides an aid to decision for economic and ecology-friendly profitability.
Mots clés Genetic distance, Genetic diversity, Sustainability, C-viability, Genetic resistance
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Résumé Price reviews are a potentially costly activity. A significant fraction of unchanged prices may stem from firms not reviewing prices, rather than from obstacles to changing prices per se, such as menu costs. In this paper, we disentangle these two causes of price stickiness by estimating an inflated ordered probit model on a panel of French manufacturing firms. The results point to a low frequency of price reviews, suggestive of the relevance of information costs as a determinant of the observed price stickiness. In view of the “inattentive producers” literature, pointing that the source of price rigidity matters, this is suggestive of a large real effect of monetary policy.
Mots clés Inflated ordered probit model, Price changes, Price reviews, Price stickiness
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Résumé In this article, we unpack Baumol’s (J Polit Econ 98(5):893–921, 1990) theory of entrepreneurship’s outcomes (productive, unproductive, and destructive) in a framework of failing institutions, considering that entrepreneurship is instead first characterized by two non-mutually exclusive types of behavior (conforming versus evasive). We hypothesize that the evasive activity (firm-level corruption) is undertaken as a second-best response to poor institutional quality, supporting the conforming activity. Using instrumental variable panel regression in the context of Indonesia, we evidence the mediating effect of bribing on the relation between local institutional quality and new business density, thus unveiling the real effect of institutional quality on entrepreneurship.
Mots clés Indonesia, Mediation, Corruption, Institutions, Entrepreneurship
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